Sewing machine



c. COLEGROVE ET L- 2,034,506

SEWING MACHINE rch 17, 1936.

Filed April 10, 1933' /N VEN Toes:

W QG 6 s w ur e 5 Wm 5A M? Aw Patented Mar. 17, 1936 UNITED STATESSEWING MACHINE Charles E. Colegrove, Lakewood, and

John A. Antel, Cleveland, Ohio Application April 10, 1933, Serial No.665,300

7 Claims.

This invention relates to improvements in sewing machines, and hasreference particularly, to bobbin cases, latching means therefor, meansfor holding the bobbins in the cases, and thread tensioning means foruse upon bobbin cases in sewing machines of the revolving shuttle,revolving hook, and oscillating shuttle types.

One of the objects of the invention is the provision of simple andeffective means for latching a bobbin case to the cover of the rotary oroscillating shuttle raceway.

Another object is the provision of novel means for retaining the bobbinin the bobbin case while the latter is being inserted into or removedfrom the shuttle, the bobbin retaining means being actuated preferablysimultaneously with the withdrawal of the retaining latch for the bobbincase.

Other objects and features of novelty will appear as we proceed with thedescription of those embodiments of the invention which, for thepurposes of the present application, we have illustrated in theaccompanying drawing, in which Figure 1 is an elevational view of ashuttle mechanism embodying the invention;

Fig. 2 is a vertical sectional view of the same taken substantiallyalong the line 22 of Fig. 1, this view being inclined slightly from thevertical, bringing the shuttle into a vertical plane, whereas in amachine it stands in a plane at a small angle to the vertical;

Fig. 3 is a top plan view of the bobbin case;

Fig. 4 is a fragmental sectional view on a larger scale, this view beingtaken substantially along the line 4 of Fig. 1.

Fig. 5 is a rear elevational view of a modified form of bobbin case.

Fig. 6 is a side elevational view of the construction shown in Fig. 5,and

Fig. 7 is a transverse sectional view taken substantially along the lineof Fig. 5.

In the drawing, a shuttle raceway is indicated at H], wherein a shuttleII is mounted to rotate. The shuttle may be driven in any known ordesired manner from a shaft |2, the driving mechanism forming no part ofthe present invention. I3 is a cover that is secured by any suitablemeans to the raceway l0, thereby holding the shuttle H in place. Theshuttle has a central stem Id.

The bobbin case, to which we have applied generally the referencenumeral l5, comprises a rear wall Is that is flat for the most part, acylindrical side wall I1, and a central hub having a portion 8 withinthe bobbin case and a portion l9 extending rearwardly from the case.

The portion 8 is hollow in order to receive rotatably the stem M of theshuttle. V

A hole is drilled diagonally through the rearwardly extending portion l9of the hub into the forward portion I8 thereof, and out in front of 5the rear wall I6 of the case. In this hole is slidably mounted a pin 20which has a rounded lower extremity or other cam surface, while theupper end of the pin is slightly enlarged to prevent its entering thehole beyond the extent il- 10 lustrated in Fig. 2.

A latch plate or finger 2| is arranged to slide radially upon the rearsurface of the bobbin case l5, being provided with a slot 22 which is ofa proper width to freely receive the rear portion 15 9 of the hub on thebobbin case. In order to hold the latch 2| against the rear surface ofthe case a collar or washer 23 is mounted upon the hub I9 behind thelatch 2|. The latch is urged radially outward by a spring 24.

The part 25 is a dome that is secured by means of screw 26 to the hubl9. At its edges this dome may be provided with tongues 21 and 28 whichfit into slots 29 and 30, thereby fixing the dome against rotation aboutthe screw 26. The 25 dome 25 holds in place the washer 23, and at itsforward end it may have inwardly turned lips 3| and 32 which act asguides to assist in holding the latch plate 2| against the rear wall ofthe case. We may attach guide strips 33 to 30 the rear wall of the caseunderneath the dome 25 on one or both sides of the latch plate 2|, forthe purpose of guiding the movements of the latter in a straight radialpath, but as will be obvious, these guides may be carried by the dome 3525 if desired. The rear end of the dome is cut away at 34 so as toprovide a thumb hold.

Just forward of the dome we strike up out of the latch plate 2| a lip35, which serves as a finger hold and latch retractor. The forward 40edge of the dome is preferably cut away at 3B in order to clear thefinger hold 35 when the latch is retracted.

We remove the corners at the forward end of the latch to provide a moreor less tapered extremity, and this extremity is deflected inwardly asshown at 31 in Fig. 2. The extremity of the latch is adapted to enter asocket or recess 38 in the cover l3, and the wall of the socket withwhich the latch engages is also beveled, as indi- 50 cated at 39, so asto impart an inward force to the latch when the operator permits it tobe extended by the spring 24. The outer surface of the cover I3 is alsobeveled at 40, so that if the latch is not retracted when the operatorinserts the bobbin case into the shuttle, the latch will be cammedbackward to pass through the opening in the cover IS, the dotted lineposition of the latch in Fig. 2 indicating how the latch approaches thebeveled surface lb when the latch is not positively retracted. When theoperator retracts the latch the head of the pin iii is engaged by therear end of the latch and the pin is forced inwardly of the bobbin caseand into tight engagement with a bobbin arranged upon the hub id. Thepin 28 thus acts to retain the bobbin in the case until the case hasbeen secured in the shuttle.

We employ a thread tensioning device which comprises a spring l! that ispreferably secured or anchored at its rear end 32 to the cylindricalwall ll of the case. This spring has a natural radius of curvature lessthan the radius of curvature of the cylindrical wall ll, so as to bearched upon that wall as indicated in Fig. 1. The thread from the bobbin(not shown) estends through a slot 43 in the case and runs along fromthe inner end of that slot beneath spring plate H to the notch 55 in thespring plate. 55 is an angle bracket which may be secured in somemanner, as by riveting, to the spring 55, and has one arm extended alongthe rear wall it of the case toward the center of the latter. In thisradial arm or bracket 35 there is an opening it which receives a cam oreccentric i? that is carried by or is integral with a short shaft 38,which is rotatably mounted in an opening in the rear wall IE of thecase. On its forward surface this wall is preferably recessed around theshaft opening in order to receive a washer l9 flush with the surface ofthe wall, and the inner end of the washer may be riveted over so as toprevent the shaft from being pulled out of the case. On its outer endthe shaft 58 has a relatively large head 55 which may be slotted to takea screw-driver, this head overhanging the opening 55. It will be obviousthat as the head 55 is rotated in one direction by means of ascrew-driver, the cam 41 will exert an inward pull on the bracket 45 andpress the spring ll toward the wall ll of the case, thereby increasingthe thread tension, and that as the cam is rotated in the oppositedirection the resiliency of the spring M will cause it to bow outwardlyagain, thereby relieving the tension. In order to assist the operator inmaking this adjustment, we may provide an index hand 55 on the head 5%of the adjusting shaft and a scale 52 on the bracket 35.

In the modification of Figs. 5, 6 and 7, we have illustrated a somewhatdifferent form of tensioning means. In these figures the bobbin casedoes not have a rearwardly extending hub portion, and the latch member53 is not retractable, but is part of a stamping which includes a bowedmember 54, having prongs entering holes in the back wall of the case,which member is fastened to the case centrally of the latter by means ofa screw 55.

The tensioning spring is more or less similar to spring ii, beingsecured to the case at one end by means of rivets 5i, and having aslightly arched portion which covers the major part of slot 43 throughthe cylindrical wall of the case. In this instance, instead of attachinga separate bracket to the spring, we form a bracket arm 58 integral withthe spring, and bend it to eX tend toward the center of the case. On itsinner extremity however it is provided with a fiange 59 which extendsinto a slot in an adjusting plate 6!. The plate 65 is provided with anaperture to loosely receive screw 55, and a spring Washer 62 tends tohold it in any given position of adjustment. The outer side of the slot68, with which the fiange 55 engages, is formed e0- centrically so as tohave a camming effect upon the flange 59 when the plate 5! is rotatedabout its pivotal mounting. A pointer arm 63 constitutes a handle bymeans of which the plate may be conveniently rotated, and alsocooperates with a gauge scale 6 on the rear wall N5 of the case forindicating the tension provided by various adjustments. It will beobvious that as the pointer arm 53 is swung toward the right in Fig. 5,the flange 58 on the inner end of bracket arm 58 will be drawn towardthe center of the case, thereby drawing the tensioning spring 56 downupon the cylindrical surface of the bobbin case and increasing thethread tension, Whereas movement of the pointer 53 toward the leftleaves the spring 55 free to bow itself outwardly again, therebyrelieving the tension.

Having thus described our invention, we claim:

1. In a sewing machine, a shuttle raceway, a cover therefor, a bobbincase, said cover having a socket therein, a radially slidable latchmounted on the outer side of the bobbin case, said latch being adaptedto enter said socket, means tending to move said latch, radiallyoutward, a finger hold projecting from said latch, and a fixedprojecticn in said bobbin case opposite said finger hold, whereby thebobbin case may be handled and the latch retracted at the same time bythe thumb finger of an operators hand.

2. In a sewing machine, a shuttle raceway, a cover therefor, a bobbincase having an outwardly extending hub, said cover having a sockettherein, a radially slidable latch provided with a slot in which thesaid hub is slidably received, the outer end of said latch being adaptedto enter said socket, means mounted on said hub overlying said latch tohold it against the outer face of the shuttle case, means tending tomove said latch radially outward, means for guiding the latch, and anoutwardly projecting finger hold on the latch by means of which it maybe retracted.

3. In a sewing machine, a shuttle raceway, a cover therefor, a bobbincase having an outwardly extending hub, said cover having a sockettherein, a radially slidable latch provided with a slot in which saidhub is slidably received, the outer end of said latch being adapted toenter said socket, a dome mounted upon said hub and having edge portionsengaging said bobbin case, spring means interposed between said case andlatch tending to move the latch radially outward, said spring meansbeing covered by said dome, and an o'utwardly projecting finger hold onthe latch in front of the dome, said dome being formed on the oppositeside to afford a thumb hold for the operator.

4. In a sewing machine, a shuttle raceway, a cover therefor, a bobbincase, said cover having a socket therein, a radially slidable latchmounted on the outer side of the bobbin case, said latch being adaptedto enter said socket, means tending to move said latch radially outward,a finger hold on the latch to facilitate its retraction, said latch andsocket having inclined engaging surfaces tending to force the bobbincase inwardly as the latch moves outwardly to operative position.

5. In a sewing machine, a bobbin case having a central inner hub, saidhub having an inclined perforation therethrough from the back of thecase to the front thereof, a pin in said perforation, a retaining latchslidably mounted on the back of the case, and means upon said latchadapted to engage the outer end of the pin and force it inwardly whenthe latch is retracted.

6. In a sewing machine, a bobbin case having a central hub extendingboth inwardly and outwardly, said hub having an inclined perforationtherethrough extending from the back of the case into the front of thecase, a pin slidably mounted in said perforation, said pin beingslightly longer than the perforation. and having a rounded innerextremity, whereby it will be cammed outwardly when a bobbin is pushedonto the inner part of said hub, a latch slidably mounted on the outersurface of the bobbin case, and having a slot therethrough for thereception of the outer portion of said hub, the latch at one end of theslot being adapted to engage the outer extremity of the pin and push itinwardly when the latch is retracted.

7. In combination, a bobbin case having a central hub extending bothforwardly and rearwardly from the rear wall of the case, said hub havinga perforation extending diagonally therethrough from behind the rearwall of the case into the interior of the case, a pin of slightlygreater length than the length of said perforation slidably mounted insaid perforation, said pin having a cam surface at its inner end,whereby it is adapted to be slid outwardly when a bobbin is pushed ontosaid hub within the case.

CHARLES E. COLEGROVE. JOHN A. AN'IEL.

